1. Field of the Invention
The present invention relates to nonwoven fabrics for cleaning cylinders of machinery, such as printing machine cylinders, especially cylinders having a textured or rough surface.
2. Description of the Related Art
It is known in the art to use nonwoven fabrics to clean the cylinders of printing machines. U.S. Pat. No. 5,974,976 to Gasparrini et al. describes nonwoven cleaning fabrics having reduced air content and the use of such fabrics to clean the cylinders of a printing press. U.S. Patent Application Publication No. 2002/0187307 to Tanaka et al. describes wet-laid sheets for cleaning printer cylinders. The wet-laid sheets contain between about 5 and 50 weight percent binder fibers and are hydroentangled and creped, followed by heating to fuse the binder fibers after creping. Examples of wet-laid sheets include sheets containing at least 60 percent pulp.
In the past, printing machines have generally been configured with three cylinders: plate, blanket, and impression cylinders. The impression cylinder is generally a smooth metal cylinder and holds the paper and presses it against the image-carrying blanket cylinder. More recently, printing machines have been designed to allow the printer to print on the second side of an already printed sheet in a single pass by replacing the smooth-surfaced impression cylinder with a cylinder having a textured (not smooth) or rough surface, which minimizes the contact points with the printed side. The textured or rough impression cylinder is optionally coated, such as with a release coating such as silicone. Uncoated textured or rough cylinders tend to be abrasive. Even the coated rolls can become abrasive as the release coating wears off over time and with use (measured as number of copies printed).
Conventional nonwoven printer cleaning fabrics containing wood-pulp have worked well for cleaning printing machines with smooth-surfaced impression cylinders but have been found to lack the durability desired for cleaning textured impression cylinders and often tear or lint in such applications. It would be desirable to provide an improved cleaning fabric for cleaning textured or rough printing machine cylinders that has high abrasion resistance and low linting while retaining sufficient absorbency to effectively remove inks, solvent, and other solid or paste-like residue from the cylinder surface such as accumulated paper lint fibers.